[core] Gate fast paths on a wait's deadline, not its existence by VaguelySerious · Pull Request #4124 · vercel/workflow

VaguelySerious · 2026-09-11T20:22:44Z

Part of #3916 (option 1). Not a full fix for that issue: the 20x regression reported there was dominated by VM retention being disabled, which #3892 addressed in beta.48. This PR covers the remaining item: a far-future open wait should not cost an extra round trip per step boundary, nor disable turbo's optimistic start.

Problem

Promise.race([hook, sleep('24h')]) where the hook wins leaves the sleep open in the event log until its timer elapses. There is no event that disposes a wait. openHookAndWaitState counted any wait_created without a matching wait_completed as open, and two fast-path gates in runtime.ts required no open wait at all:

requestInlineDelta: when false, the runtime falls back to an incremental events.list() per step boundary.
forceOptimisticStart (turbo): when false, inline steps take the await-then-run path.

So a single lost 24h sleep put the rest of the run on the slow path.

Change

wait_created.eventData.resumeAt is durable and already in the log. The open-hook/wait scan (moved to runtime/open-hook-wait-state.ts, exported for tests) now records the earliest open wait deadline, and the two gates ask hasImminentOpenWait(state, Date.now()) instead of openWait. A wait is imminent when its deadline is within IMMINENT_WAIT_HORIZON_MS of the gate's clock, already past, or unreadable.

openWait keeps its old "any open wait" meaning; the continueOverHookWrite read-before-resume check still uses it and is unchanged here (it has the same rationale and is a candidate for the same treatment, but it is out of scope for this PR).
Hook gating (openHook) is untouched.
getRetentionDecision does not look at waits (since [core] Retain workflow VMs across waits #3892) and this PR does not add that back.

Horizon

IMMINENT_WAIT_HORIZON_MS = 30_000, override WORKFLOW_IMMINENT_WAIT_HORIZON_MS. Reasoning, also in the constant's comment:

Inline delta: the delta is taken at the step's terminal write and includes events interleaved before it, so the only exposure is the gap between that commit and where the fallback events.list() would have run. That is milliseconds inside one invocation.
Turbo: the invocation a wait can spawn is its timer's resume. A resume that arrives after this batch's step_started claims have landed replays over them rather than racing for them, so the exposure is the claim's round trip.
On top of that: the wait timer's queue can deliver a continuation early (the runtime already tolerates 2s of this via NEAR_ELAPSED_WAIT_THRESHOLD_SECONDS), and the host writing wait_completed has its own clock skew. Seconds at most.

30s covers those with an order of magnitude of margin while still leaving a sleep('1m') racing a hook on the fast path for its first half. A very large override restores the old unconditional gating.

Why the downside is bounded

The guarantee is on the timer's writer, not every writer: force-completing a pending wait ignores resumeAt. If such a wait_completed lands after the step's terminal write, it is absent from that write's delta and the next read observes it instead. In events-consumer.ts, wait_completed is in both PARKABLE_EVENT_TYPES (parked until the replay reaches the wait) and ONE_SHOT_EVENT_TYPES (a second resolution for the same id is refused rather than parked), so a late-observed completion is absorbed, not lost. This is the same shape as the read-to-write race the fetch path already has: the stale view is a prefix of the log, never a hole in it.

Conservative defaults

A wait_created whose resumeAt is missing or unparseable is treated as due now (-Infinity), so the gate is never less safe than before for a wait it cannot reason about.

Tests

packages/core/src/runtime/open-hook-wait-state.test.ts:

far-future wait does not gate; same wait with an imminent resumeAt does (boundary at exactly the horizon)
wait past its resumeAt gates
missing / unparseable resumeAt gates
completed wait never gates, whatever its deadline
several waits: earliest deadline wins; completing the near one lifts the gate
gate re-engages as the clock approaches a far deadline
hooks: openHook unaffected by waits in either direction
env override default and a large override restoring unconditional gating

cd packages/core && pnpm test: 113 files, 2446 tests passed.

Docs

WORKFLOW_IMMINENT_WAIT_HORIZON_MS added to docs/content/docs/v5/configuration/runtime-tuning.mdx.

🤖 Generated with Claude Code

An open wait suppresses the per-step inline event delta and turbo's forced optimistic start. Nothing disposes a wait, so a `sleep()` that lost a `Promise.race()` against a hook stayed open until its timer elapsed and held every later step boundary of the run on the slow path. `wait_created` carries a durable `resumeAt`. The open-hook/wait scan now records the earliest open deadline, and the two gates consult it against the gate's own clock: a wait due beyond `IMMINENT_WAIT_HORIZON_MS` (default 30s, `WORKFLOW_IMMINENT_WAIT_HORIZON_MS`) cannot produce a `wait_completed` during the boundary being scheduled, so it does not gate. A wait already due, or one whose `resumeAt` cannot be read, gates as before. Hook gating is unchanged. Refs #3916 Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

changeset-bot · 2026-09-11T20:22:50Z

🦋 Changeset detected

Latest commit: fce9bbd

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 16 packages

Name	Type
@workflow/core	Patch
@workflow/builders	Patch
@workflow/cli	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/vitest	Patch
@workflow/web-shared	Patch
@workflow/web	Patch
workflow	Patch
@workflow/world-testing	Patch
@workflow/astro	Patch
@workflow/nest	Patch
@workflow/rollup	Patch
@workflow/sveltekit	Patch
@workflow/vite	Patch
@workflow/nuxt	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

vercel · 2026-09-11T20:22:51Z

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated
example-nextjs-workflow-turbopack	Ready	Preview, v0	Sep 11, 2026 8:25pm UTC
example-nextjs-workflow-webpack	Ready	Preview, v0	Sep 11, 2026 8:25pm UTC
example-workflow	Ready	Preview, v0	Sep 11, 2026 8:25pm UTC
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workflow-web	Ready	Preview, v0	Sep 11, 2026 8:25pm UTC

github-actions · 2026-09-11T20:23:03Z

📊 Workflow Benchmarks

commit fce9bbd · Fri, 11 Sep 2026 20:48:44 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	194 (-16%) 💚	1644 🔴 (+21%) 🔻	1696 🔴 (+23%) 🔻	2000 🔴 (+38%) 🔻	30
TTFS	stream	184 (+12%)	1644 🔴 (+21%) 🔻	1720 🔴 (+21%) 🔻	1920 🔴 (+17%) 🔻	30
TTFS	hook + stream	1297 (+157%) 🔻	2063 🔴 (+12%)	2076 🔴 (+4.2%)	2310 🔴 (±0%)	30
Fan-out TTFS	Promise.all(100 steps)	568 (-15%) 💚	920 (+14%)	2547 (+169%) 🔻	2593 (+29%) 🔻	10
Fan-out TTLS	Promise.all(100 steps)	1879 (-4.5%)	6253 (+144%) 🔻	8109 (+80%) 🔻	9232 (+30%) 🔻	10
STSO	1020 steps (inline)	120 (-2.4%)	163 (+2.5%)	184 (+2.2%)	299 (-11%)	1019
WO	1020 steps	161512 (+1.3%)	161512 (+1.3%)	161512 (+1.3%)	161512 (+1.3%)	1
CRTT	first chunk (pooled)	63 (±0%)	109 (-13%)	131 (-21%) 💚	142 (-69%) 💚	28

Streams

Scenario	CRTT 1st	p75	p90	p99	CDV max	iters
paced control (100/s, 60B)	87 (-6%)	186 (-51%)	260 (-44%)	432 (-57%)	153 (-65%)	10
size sweep (100/s, 160B-12KB)	84.5 (-10%)	208 (-51%)	609 (-34%)	940 (-36%)	184 (-48%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	121 (-5%)	150 (-20%)	217 (-16%)	547 (-12%)	183 (-65%)	3
replay eve-gpt-5.6-sol-2000t (1x)	88 (-17%)	145 (-16%)	217 (-6%)	745 (+43%)	745 (+78%)	2
replay eve-gpt-5.6-sol-2000t (2x)	116 (+18%)	219 (-30%)	313 (-36%)	742 (-34%)	286 (-28%)	3

📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 159219ms → this run 161318ms (Δ +2099ms, +1%)

100-150 ms  ████████████████████┃███  main 595  this 519   -76
150-200 ms  ███████████████░┃         main 372  this 432   +60
200-250 ms  █┃                        main  31  this  46   +15
250-300 ms  ┃                         main   6  this  12    +6
300-350 ms  ┃                         main   8  this   2    -6
350-400 ms  ┃                         main   2  this   4    +2
400-450 ms  ┃                         main   1  this   2    +1
450-500 ms  ┃                         main   1  this   2    +1
550-600 ms  ┃                         main   2  this   0    -2
600-650 ms  ┃                         main   1  this   0    -1

📈 CRTT drill-down vs main (RTT distributions & profiles)

variant  RTT 1ms→5s+             avg         p50         p90         p99     n
control  ······▃█▂····  138.4 (-39%)  126 (-14%)  260 (-44%)  432 (-57%)  3000
sweep    ······▃█▂▁···  168.7 (-34%)  126 (-32%)  609 (-34%)  940 (-36%)  3000
gw 1x    ·····▁▄█▁▁···  127.1 (-18%)  114 (-18%)  217 (-16%)  547 (-12%)  5295
eve 1x   ·····▁▅█▂▁▁··     135 (-8%)  113 (-14%)   217 (-6%)  745 (+43%)  5186
eve 2x   ·····▁▂█▄▁···  176.9 (-25%)  153 (-17%)  313 (-36%)  742 (-34%)  7779

RTT over stream progress (avg per tenth of stream, bars scaled min→max):

control  ▂▄█▄▃▂▄▃▄▁  125–163ms
sweep    █▆▅▂▁▁▂▄▆▅  128–225ms
gw 1x    ▃▃█▄▃▃▃▁▂▅  104–167ms
eve 1x   ▃▂▃▂▁▅▅▇▃█  99–190ms
eve 2x   ▄▁▃▄▁█▅▅█▃  140–222ms

RTT by chunk size (avg per log size bin, ~160B → ~12KB serialized, bars scaled min→max):

sweep  ▃██▆▇▂▁  166–171ms

Delivery jitter over stream progress (avg positive CDV per tenth of stream, bars scaled min→max):

control  ▃▆▆▃█▁▇▂▅▂  39–48ms
sweep    █▅▃▁▂▃▄▆▃▅  49–85ms
gw 1x    ▄▄█▄▃▆▃▁▂▄  32–44ms
eve 1x   ▃▃▁▁▁▄▅▆▂█  23–36ms
eve 2x   █▃▄▅▂▆▃▁▄▃  23–36ms

ℹ️ Metric definitions & methodology

_{Streams: first-chunk RTT (the stream-open path, before any buffering/backpressure), CRTT percentiles, and worst delivery stall (CDV max). Cells are medians across iterations; per-run values in the artifacts. No 🔴/🟢 marks until targets attach.}

_{The collapsed STSO distribution section above buckets every step gap, split inline (same warm process — pure framework overhead) vs queue-hop (fresh process — dispatch, reinit, replay). █ = main, ┃ = this run, ░ = fill.}

_{The collapsed CRTT drill-down: per-variant RTT histograms (fixed log bins, · = empty) and mean RTT/positive-CDV profile lines over stream progress and chunk size. Histograms, avgs, and profiles merge exactly across runs; p50–p99 are percentile-of-percentiles. Per-index rows live in the artifacts.}

_{Best/P75/P90/P99 deltas compare against the most recent benchmark run on main at the time of this run. 🔻 flags a delta worse than +15%, 💚 one better than −15%.}

_{Metrics — TTFS: time to first step body (in-deployment start() → first step body) · Fan-out TTFS: fan-out time to first step (in-deployment start() → first of the parallel step bodies to complete) · Fan-out TTLS: fan-out time to last step (in-deployment start() → last of the parallel step bodies to complete, i.e. when the Promise.all resolves) · STSO: step-to-step overhead (gap between consecutive step bodies) · WO: workflow overhead (whole-run time outside step bodies, in-deployment anchored) · CRTT: chunk round-trip time (per-chunk write → read latency, one clock domain: deployment → stream backend → same deployment) · CDV: chunk delay variation / delivery jitter (inter-arrival gap minus inter-write gap per seq-adjacent pair; skew-free; the row is each run's MAX positive value, so one stall moves it)}

_{Scenarios — step: one trivial no-op step, no stream; no hooks, so the run stays in turbo mode (in-process fast path) · stream: one streaming step; no hooks, so the run stays in turbo mode (in-process fast path) · hook + stream: registers a hook before one step, which exits turbo mode (dispatch path) · 1020 steps: 1020 trivial sequential steps; STSO is measured between consecutive steps in the given step ranges, and WO is the whole-run overhead outside step bodies · Promise.all(100 steps): 100 trivial no-op steps started together in a single Promise.all; Fan-out TTFS is the first of them to complete and Fan-out TTLS the last, both from the in-deployment clientStart, so their gap is the spread the runtime adds across the fan-out · paced control (100/s, 60B): the control: 300 tiny (~60B) deltas metronome-paced at 100/s — zero workload structure, so it reads the transport floor and flush cadence, and disambiguates transport-wide vs workload-specific when a replay row moves · size sweep (100/s, 160B-12KB): same pacing as the control with deltas padded in rotation across seven log-spaced sizes (~160B–12KB) — rotation decouples size from stream position, so it isolates whether chunk size causes latency · replay gateway-gpt-5.4-nano-2000t (1x): raw provider SSE cadence captured at the AI gateway boundary (gpt-5.4-nano, the most popular gateway model; per-token deltas p50 208B = the modal production chunk size), replayed exactly as measured — the typical customer's workload; its CDV is the typical customer's real delivery jitter · replay eve-gpt-5.6-sol-2000t (1x): a captured eve turn (gpt-5.6-sol, the most-used demanding eve model; ~2000 output tokens = production p50 turn length) replayed exactly as measured — eve's envelope protocol re-ships the cumulative message so sizes ramp 142B→13KB; the demanding outlier tenant's reality · replay eve-gpt-5.6-sol-2000t (2x): the same eve capture at 2x — the headroom/stress row; real fast-tier models emit the same chunk sizes at proportionally higher rate, so time compression is a faithful speed model · first chunk (pooled): every run's seq-0 RTT pooled across all stream scenarios — the first chunk precedes any workload differentiation, so pooling samples one shared stream-open path with exact percentiles}

_{Replay cadences (semantic sha256) — eve-gpt-5.6-sol-2000t eaf22f5946e7c61f3c65c7006d550df180cfabd4e706254a09f22aec0cfb420d · gateway-gpt-5.4-nano-2000t 6f24ac518b6b83ff1d0e85a5fe78230db192716d66a7fc6b2fe022752001d041}

_{🔴 marks a percentile over its target (within target is left unmarked). Targets (p75/p90/p99, ms) — TTFS 200/300/600}

_{All timestamps are deployment-side; runs are triggered in-deployment, so the CI runner and api.vercel.com sit outside every measured window. TTFS = start() → first step body (includes dispatch + any cold start); Fan-out TTFS/TTLS = first/last step completion of one Promise.all from the same anchor (the gap is the runtime’s fan-out spread); STSO/WO between step bodies; CRTT inside the workflow (excludes the api.vercel.com read path).}

_{Cold starts stay in the numbers (real bursty-workload latency, inflates P75+); Best is the warm floor.}

github-actions · 2026-09-11T20:23:03Z

🧪 E2E Test Results

✅ All tests passed

⚠️ Flaky E2E Tests (passed on retry)

These tests failed at least once and passed on a retry. A recurring entry here is a real race worth investigating.

promiseAllWorkflow (tanstack-start)
promiseRaceWorkflow (fastify)

🛠 Infra Events (absorbed by the harness)

Platform anomalies the e2e harness detected and worked around (e.g. a run the queue never picked up, replaced by a fresh run). Clustered timestamps indicate a backend blip; a steady drip indicates a platform issue worth escalating.

cold-start-warmup · suite warmup (tanstack-start) · at 20:28:17Z · abandoned wrun_01M292FGYNP8MXBQ4B5ECDZ7WT
run-pickup-stall · hookCleanupTestWorkflow - hook token reuse after workflow completion (nextjs-webpack) · at 20:33:09Z · abandoned wrun_01M292RNFBYZ1M0QSQ1CBQ1V32
run-pickup-stall · concurrent hook token conflict - two workflows cannot use the same hook token simultaneously (nextjs-webpack) · at 20:33:09Z · abandoned wrun_01M292RNNG2V3ARQHXGJMGJR39

E2E Test Summary

Summary

	Passed	Skipped	Total
✅ ▲ Vercel Production	3662	685	4347
✅ 💻 Local Development	3922	586	4508
✅ 📦 Local Production	3922	586	4508
✅ 🐘 Local Postgres	3922	586	4508
✅ 🪟 Windows	320	2	322
✅ 🌐 Cross-language Conformance	68	74	142
✅ vercel-http-transport	823	143	966
✅ vercel-multi-region	27	0	27
✅ vercel-ws-transport	557	87	644
Total	17223	2749	19972

Details by Category

✅ ▲ Vercel Production

App	Passed	Skipped
✅ astro-node	133	28
✅ astro-quickjs	133	28
✅ example-node	133	28
✅ example-quickjs	133	28
✅ express-node	133	28
✅ express-quickjs	133	28
✅ fastify-node	133	28
✅ fastify-quickjs	133	28
✅ hono-node	133	28
✅ hono-quickjs	133	28
✅ nest-node	133	28
✅ nest-quickjs	133	28
✅ nextjs-turbopack-node	158	3
✅ nextjs-turbopack-quickjs	158	3
✅ nextjs-webpack-node	158	3
✅ nextjs-webpack-quickjs	158	3
✅ nitro-node	133	28
✅ nitro-quickjs	133	28
✅ nuxt-node	133	28
✅ nuxt-quickjs	133	28
✅ python-node	66	95
✅ sveltekit-node	152	9
✅ sveltekit-quickjs	152	9
✅ tanstack-start-node	133	28
✅ tanstack-start-quickjs	133	28
✅ vite-node	133	28
✅ vite-quickjs	133	28

✅ 💻 Local Development

App	Passed	Skipped
✅ astro-stable-node	134	27
✅ astro-stable-quickjs	134	27
✅ express-stable-node	134	27
✅ express-stable-quickjs	134	27
✅ fastify-stable-node	134	27
✅ fastify-stable-quickjs	134	27
✅ hono-stable-node	134	27
✅ hono-stable-quickjs	134	27
✅ nest-stable-node	134	27
✅ nest-stable-quickjs	134	27
✅ nextjs-turbopack-canary-node	141	20
✅ nextjs-turbopack-canary-quickjs	141	20
✅ nextjs-turbopack-stable-node	160	1
✅ nextjs-turbopack-stable-quickjs	160	1
✅ nextjs-webpack-canary-node	141	20
✅ nextjs-webpack-canary-quickjs	141	20
✅ nextjs-webpack-stable-node	160	1
✅ nextjs-webpack-stable-quickjs	160	1
✅ nitro-stable-node	134	27
✅ nitro-stable-quickjs	134	27
✅ nuxt-stable-node	134	27
✅ nuxt-stable-quickjs	134	27
✅ sveltekit-stable-node	153	8
✅ sveltekit-stable-quickjs	153	8
✅ tanstack-start-node	134	27
✅ tanstack-start-quickjs	134	27
✅ vite-stable-node	134	27
✅ vite-stable-quickjs	134	27

✅ 📦 Local Production

App	Passed	Skipped
✅ astro-stable-node	134	27
✅ astro-stable-quickjs	134	27
✅ express-stable-node	134	27
✅ express-stable-quickjs	134	27
✅ fastify-stable-node	134	27
✅ fastify-stable-quickjs	134	27
✅ hono-stable-node	134	27
✅ hono-stable-quickjs	134	27
✅ nest-stable-node	134	27
✅ nest-stable-quickjs	134	27
✅ nextjs-turbopack-canary-node	141	20
✅ nextjs-turbopack-canary-quickjs	141	20
✅ nextjs-turbopack-stable-node	160	1
✅ nextjs-turbopack-stable-quickjs	160	1
✅ nextjs-webpack-canary-node	141	20
✅ nextjs-webpack-canary-quickjs	141	20
✅ nextjs-webpack-stable-node	160	1
✅ nextjs-webpack-stable-quickjs	160	1
✅ nitro-stable-node	134	27
✅ nitro-stable-quickjs	134	27
✅ nuxt-stable-node	134	27
✅ nuxt-stable-quickjs	134	27
✅ sveltekit-stable-node	153	8
✅ sveltekit-stable-quickjs	153	8
✅ tanstack-start-node	134	27
✅ tanstack-start-quickjs	134	27
✅ vite-stable-node	134	27
✅ vite-stable-quickjs	134	27

✅ 🐘 Local Postgres

App	Passed	Skipped
✅ astro-stable-node	134	27
✅ astro-stable-quickjs	134	27
✅ express-stable-node	134	27
✅ express-stable-quickjs	134	27
✅ fastify-stable-node	134	27
✅ fastify-stable-quickjs	134	27
✅ hono-stable-node	134	27
✅ hono-stable-quickjs	134	27
✅ nest-stable-node	134	27
✅ nest-stable-quickjs	134	27
✅ nextjs-turbopack-canary-node	141	20
✅ nextjs-turbopack-canary-quickjs	141	20
✅ nextjs-turbopack-stable-node	160	1
✅ nextjs-turbopack-stable-quickjs	160	1
✅ nextjs-webpack-canary-node	141	20
✅ nextjs-webpack-canary-quickjs	141	20
✅ nextjs-webpack-stable-node	160	1
✅ nextjs-webpack-stable-quickjs	160	1
✅ nitro-stable-node	134	27
✅ nitro-stable-quickjs	134	27
✅ nuxt-stable-node	134	27
✅ nuxt-stable-quickjs	134	27
✅ sveltekit-stable-node	153	8
✅ sveltekit-stable-quickjs	153	8
✅ tanstack-start-node	134	27
✅ tanstack-start-quickjs	134	27
✅ vite-stable-node	134	27
✅ vite-stable-quickjs	134	27

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack-node	160	0	1
✅ nextjs-turbopack-quickjs	160	0	1

✅ 🌐 Cross-language Conformance

App	Passed	Failed	Skipped
✅ python	68	0	74

✅ vercel-http-transport

App	Passed	Skipped
✅ example	133	28
✅ express	133	28
✅ hono	133	28
✅ nextjs-turbopack	158	3
✅ nitro	133	28
✅ vite	133	28

✅ vercel-multi-region

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

✅ vercel-ws-transport

App	Passed	Skipped
✅ example	133	28
✅ express	133	28
✅ nextjs-turbopack	158	3
✅ vite	133	28

📋 View full workflow run

github-actions · 2026-09-11T20:26:37Z

Sim World

Simulated world deterministic testing for races. Traces

🟠 world-sim scenario book — 1 fail of 41 total

fence=per-spec

scenario	outcome	events	virt	replay
✅ `smoke-no-steps`	completed	3	0ms	ok
✅ `smoke-one-step`	completed	6	0ms	ok
✅ `hook-at-step-started`	completed	12	0ms	ok
✅ `hook-at-step-completed`	completed	12	0ms	ok
✅ `hook-at-hook-created`	completed	12	0ms	ok
✅ `deadline-hook-wins`	completed	7	1.0h	ok
✅ `deadline-expires`	completed	7	1.0h	ok
✅ `long-sleep`	completed	11	30.0d	ok
✅ `hook-never-arrives`	stalled	3	0ms	skipped
✅ `step-retries-twice`	completed	10	2.0s	ok
✅ `parallel-steps`	completed	9	0ms	ok
✅ `hook-on-execution-state`	completed	12	0ms	ok
✅ `peek-hook-before-branch`	completed	12	0ms	ok
✅ `peek-hook-after-branch`	completed	12	0ms	ok
✅ `peek-hook-at-registration`	completed	12	0ms	ok
✅ `race-hook-before-probe`	completed	12	0ms	ok
✅ `race-hook-after-probe`	completed	12	0ms	ok
✅ `race-duplicate-delivery`	completed	13	0ms	ok
✅ `attr-hook-before-step`	completed	11	0ms	ok
✅ `attr-hook-after-step`	completed	11	0ms	ok
✅ `attr-from-step-body`	completed	13	0ms	ok
✅ `fork-hook-after-timeout`	completed	14	1.0m	ok
✅ `fork-hook-before-timeout`	completed	14	1.0m	ok
✅ `count-hook-after-timeout`	completed	17	1.0m	ok
✅ `count-hook-before-timeout`	completed	20	1.0m	ok
✅ `stale-read-step-count-fork`	completed	20	1.0m	ok
✅ `stale-read-equal-step-counts`	completed	14	1.0m	ok
✅ `step-vs-step-fork`	completed	12	0ms	ok
✅ `step-vs-step-fork-fenced`	completed	12	0ms	ok
✅ `fence-catches-benign-direction`	completed	12	5ms	ok
✅ `in-flight-before-decision`	completed	17	1.0m	ok
❌ `in-flight-before-decision-counted`	completed	17	1.0m	ok
✅ `in-flight-after-decision`	completed	19	2.0m	ok
✅ `stale-read-step-count-fork-fenced`	completed	20	1.0m	ok
✅ `fork-hook-wins`	completed	13	1.0m	ok
✅ `fork-timeout-wins`	completed	13	1.0m	ok
✅ `unclaimed-payload-under-fork`	completed	17	1.0m	ok
✅ `claimed-payload-under-fork`	completed	17	1.0m	ok
✅ `writers-independent-step-bodies`	completed	12	0ms	ok
✅ `writers-scripted-tempo`	completed	12	0ms	ok
✅ `cancel-mid-step`	cancelled	7	0ms	skipped

Full trace: world-sim.txt

github-actions · 2026-09-11T20:27:44Z

Framework	Flow route	Step reg.	Framework output
hono	236.0 KiB (±0)	42.3 KiB (±0)	1.81 MiB (+824 B)
nextjs-turbopack	242.2 KiB (±0)	439 B (±0)	837.9 KiB (+191 B)

About these numbers

Sizes are gzip; parentheses show the change against main.
Flow route and Step reg. gate this job, on raw bytes rather than the gzip shown, at max(2%, 50.0 KiB). Framework output is informational.

fce9bbd · run

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[core] Gate fast paths on a wait's deadline, not its existence - #4124

[core] Gate fast paths on a wait's deadline, not its existence#4124
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